Devilbiss has variety of size cups for those gun's.
https://www.autorefinishdevilbiss.com/p ... -cups.aspxYour probably gonna want a new seal kit, I would.
https://www.autorefinishdevilbiss.com/p ... parts.aspxDevilbiss guns like fresh seals, You can get away with reusing them for a while in between cleanings but they will require replacing eventually if not frequently depending on use.
How careful you are removing them, cleaning them and how careful you are too not over tighten them.
especially the Needle packing's! keep it lubed not too tight not too loose.
You want it tight enough not too leak but you want the needle to slide without binding on the Needle so it slides freely. They are known to drip from the Needle packing if not carefully cared-for.
If this is a brand new set make sure to disassemble and clean them thoroughly before use!