Is actually a problem endemic to all PRV's, not DeLoreans (are there even any 7mm bolts on remainder of car?)
If you ever do strip 7x1mm bolt hole, 5/16-24 taps VERY nicely as a replacement. 1mm pitch translates into slight fraction more than 24 TPI. Tap will follow remaining threads as easily as bolt itself.
7mm hardware from industrial suppliers, but you need to order in bags of 100. My local NAPA sells individually (grade 8.8), but cost about 45 cents each.
Bill Robertson #5939