After 314 K miles on my '95 Legacy Outback, my hill holder return spring has gotten weak and will not return the crank pulley far enough to release the valve at times. i checked with the dealer but they want a couple hundred dollars for a whole new hill holder assembly, but all it really needs is a new spring. I've considered going to the hardware store finding something comparable and making my own but would like to get a Subaru spring if possible. Any body have a source for just the spring?

Lube the cable and valve.  If it still fails to return get a used one from one of the rust free parts of the country.

It's probably the cable. Fish the cable out, load it up with Garage door lube, or cable oil if you can find it.

No I had the whole unit out and the cable moves freely, also it is easy to rotate the bell crank the last 10-15 degrees by hand to get the valve to release. I just shortened the existing spring to add more tension and it works fine again but I don't know how long the spring will last with added tension and stretch. I may have to check local junkyards to see. I live in SoCal so rust is not a big issue.