I buy parts when I am fixing for others, but if I didn't hack\cnc alternate\new parts, my old machines wouldn't be running as parts being NLA.
I actually get alot of oldies\goodies because the shops are firm with your attitude. A Western Auto tiller only needed a new 10" wheel which to the shop is NLA, as that was the only thing wrong with it. They left it out for trash, fresh gas, it started on 2 pulls. If I ran a shop, like my posts, I would offer the owner alternatives- in this one case u can get a wheel that fits at Home Depot or online for less.