I've had good results getting them for my '67 and '65 from junkyard cars, like $5 for a handful. A bit rusty, but fixed that with some homemade rust remover and followed up with Eastwood phosphate brew. The molded repop pad for my '67 took all of 15 minutes to install.

Maybe I should start flippin' insulation pad clips?

65 Satellite hardtop 361/4bbl console 727 2.76
67 Satellite convert 383/2bbl column 727 3.23
67 Lancia Fulvia Sport 1.3 Zagato. Alloy body, 1.3L V4 DOHC 4-spd
67 Lancia Fulvia Rallye 1.3. Alloy panel, 1.3L V4 DOHC 4-spd
71 Alfa Romeo GT Junior 1300 Zagato, 1.3L 4cyl DOHC hemi 5-spd
82 Alfa Romeo GTV6 2.5L SOHC hemi V6 5-spd transaxle
75 Maserati Bora US spec 4.9L DOHC hemi V8 5-spd ZF
77 Maserati Khamsin Euro spec 4.9L DOHC hemi V8 5-spd ZF
07 Aston Martin DB9 6.0L DOHC V12 6spd transaxle