Looking for advice for a unique familiar for a chain celestial warlock

[BloodSnake'sCha]

Hello guys :)

stuff happen and our Fiend warlock is now a Celestial warlock of Hoar and we are looking for a familiar for him.

The DM said no evil creatures, CR1 maximum and small or tiny.
no overpowered stuff like pixie.

for now I recommended:
valenar-hawk variant 1 or 6
boggle
killmoulis

Tressym - recommended by someone else

Do you guys have any idea?

[Iku Rex]

Well, pseudodragon or sprite are the by-the-book options.

A Flying Sword (CR 1/4, Small, unaligned), maybe re-fluffed as a javelin, could work.