Spring? He needs a roll pin, not a spring. But as far as springs go, the list indicates that the bolt catch spring is identical.
What I hated about building my DMR was the lack of one standard. low profile rail, high rail, LR308, AR10 AR308 KAC DPMS1 DPMS2 I mean W the actual F.
BTW @DirtyDigz I wuz gonna dig through my spare parts drawer cuz I have a DPMS1 AR and see if I have that pin but realized my catch does not use a pin, it uses an allen screw.
Thanks Scorp. I found a contact on reddit for PSA, have asked him if the roll pin is sold separately or is the same as AR15, will probably get an answer tomorrow.