My experience is most of the spoke length calculators do have specs for all the older gear. Still, doing it yourself is a good learning exercise.
For spokes, my most recent order was from
lkspoke@yahoo.com He does sell on E-prey, but I went direct. He will cut to precise measure, which I really like. His name is Lee K.If only for example: 36 x 272.2 Silver J-bend Double butted spokes @ $0.67 each came to US$24.12. This was for the front. Rear spokes were split by measurement, but also @ $0.67. 72 12mm Silver Brass spoke nipples @ $0.11 each came to $7.92.
I found that he was very nice to deal with.
I used to know a great cheap shop, but they’re gone now, too. Sigh.