1971 1302S. Advice on stock front brake pads

I looked at the front disc brake pads. They are stock type discs. The pads have worn more on the leading side, making the pad material tapered by about 1mm. There is an average of 4mm pad material left. Should I
Leave it for now
Swap pads to have thicker section leading edge
Put new ones on urgently

sounds like sticking piston in one side of calliper

Are they an easy caliper to rebuild? I assume just an O ring on the pistons, and a dust boot outer. Dissassemble, check bores for pits, grooves or sharp bits. I could take them off and get one of the mechanics at work to do it for a 6 pack of fine brew.

Check that the pistons are in the right way, the set I just pulled off my car had the shims in wrong on one side and the leading edge was the wrong way up. Caliper kits are very cheap, whole calipers aren't much either really.

if you can get classic vw on the phone, i think they had calliper's for about $70ea and the come with new pads

Yes, they are cheap, but non brand calipers and shit quality pads...rebuild kit is about the half price of the caliper and no pads...take your pick...