I checked over at autohausAZ, and the 1.5/early1.6 diesels used the same size headbolts as the 1.7 gasser.
This page on the headbolts.com site:
http://headbolts.com/volks.html shows 1.5, 1.6, 1.7, 1.8 gassers all use the same headbolt so I'm thinking the 204-4203 ARP headbolts (for the 1.8/2.0, 8 valve), should fit the 1.7 gasser and the 1.5 diesel....
or do we want the, "12 pt nuts with under cut studs 204-4701"?
It's kinda weird, he names the 1.5, 1.6, 1.7, 1.8 as all using the same headbolt but the head studs are for the 1.8 and 2.0, 8 valvers,... so do the headbolts for the 8 valve; 1.5, 1.6, 1.7, 1.8 fit the 2.0?
He has some work to do, getting the site straightened out but he's getting there. I emailed him but ARP didn't give him that info, so we need to help him with that research.