I see that there is a bloodsail mog , I am exalted with them , and it seems i have lost my uniform, or one of them bloody pirates stole it …bloody pirates can’t trust’em . so maybe they can send me a new one, or have a vendor where i can get it or maybe they do some where? … would be nice to have that since i know i really don’t feel like doing that again on a another toon …
Thank you, and be safe
Vendor should be on the ship south the bloodsail beach area.
found 2 gun vendors on ships, 1 murloc sword vendor on ship, and 1 guy on the beach selling tailoring supplies
If you did the quest and discarded the gear a while ago, a GM will probably restore it for you if you put in a ticket.
The zone is a lvl 10-30 zone, perhaps making an allied race should be enough to start the questline? 
You can open up a ticket and ask to have them restored, that’s what I did and they sent the quest rewards in the mail. I opened the ticket with the character name I completed the quests on. They did send an automated response first, just don’t mark it as resolved and say you still need help and 2 days later I got this:
A Game Master resolved your ticket, and left the following response:
Ahoy there!
Tis be a long time for a meetin’, pious Admiral Awnastasia.
I be GameMaster Rothnisas and I be wishin’ you good winds, lass.
Ye be gettin’ word that yer stripe’s not in wearin’ fashion after all that time since ye got them.
Never fear, ye can lend a hand (or hook) when it happens. A new set of threads 'n a new Hat were sent yer way in the Mail.
If ye needs anythin’ else, fell free t’ call us again.
Fair seas 'n dry powder in yer cannons fer 'em Sea Snakes.
Yers mighty, GameMaster Rothnisas
Regards,
Blizzard Support
There is no vendor, the items are quest rewards. Wowhead shows there being an NPC but it’s out of date info. I tried that first before opening my ticket.
If I remember correctly the set is a reward from the quest “Avast ye admiral!”
If it’s gone you can have a GM get you the set back since you’re flagged for completing it without too much trouble on the character you completed the quest with. Might take a while though.
What kind of rapscallion scallywag goes and looses their outfit, don’t you know the respect the pirate dress code?
That said, https://www.wowhead.com/news/a-pirates-life-how-to-get-the-bloodsail-buccaneers-cosmetic-transmog-331497#news-post-331497 has some good directions to earning it if one doesn’t have the rep, or the specific quest to do if one has it.
That said if you’ve already done the dressing the part quest, and don’t still have the white items that were in the bag after doing it, you may have to do it again, or open a ticket as has been suggested above.
Edit: That said for the clothes, the hat should be already in collections as it was a green before.
Something that happened to me, worth checking:
I acquired the set a decade ago. Back then it was actual gear. At some point I decided to store it in my Void-Storage and forgot about it.
Since my character is Plate, it never “registered” in my transmog Tab when the technology changed. It sat there forever, unlearned.
Now the items are “cosmetic”, so I got them from the Void-Storage and learned them. They disappear physically but are now in my Transmog collection for good.
Check your banks if they are not lying around. Otherwise, open ticket.
Weird I remember the 2 vendors on the ship way back they must removed them it was the 2 ship on south side of booty bay.
Like pre cata my info is out of date for sure my bad.
yes this is what i did, and the restored my clothing, and gave me the hat again, it was nice took them about 4 hours to get back to me, which is very speedy.
Thank you all for the help, 
, so yeah just open a ticket, with toon the completed it and they restore your items , happy sailing ye bloody pirates