I went to a spring manufacturer yesterday and got some cheap replacement.
cheap but stainless
In the event it happens to someone else, some specs:
coil thickness: 2.5mm
# of coils: 14
spring length: 34mm (fully compressed, all coils in contact)
hook length: about 10mm
He didn't have 34ish mm springs, but we found some 50mm springs, with 2mm thick coil.
I've installed 2 and they do a great job (they're extended to about 100/120mm once in place on the side-stand anyway)
I bought 2 spares (just in case, and I like having spares)
4 springs: 14 euros.
that's good value in my book
I'll add some pictures tonight