Where might I find a hairspring for this clock? I fortunately have a working clock identical to this one. I'm just learning to work on clocks and have enjoyed these discussions. I'm a retired engineer and welcome challenges. Most hairsprings have too small collets. Can they be drilled out to make fit? (I think not) What is the proper method for placing the hairspring onto the balance wheel? Is it possible to really restoring this assembly? Thanks for any help.