Well, I didn't actually know about them either before last night, but now we both learned something. I've got a bit of a thing for trucks, and I found these interesting. Too bad you didn't realize about the PRR car at Strasburg though, I guarantee that those frames have at least a foundry mark on them, and they may (probably) actually say ASF along with the mark. No worries though.
I don't know if you are printing with an FDM printer or with a resin printer, but you can probably print the springs. I've printed springs with FDM previously, and they behaved like the real thing. Although they were at 1/10 scale rather than 1/48. I also know that springs printed by Shapeways in FXD at 1/48 behave properly as well. So printing might be a viable option.
Coincidentally, I need pictures of an odd and specific truck in Strasburg, although mine is at the railroad rather than the museum. The ex-Philadelphia & Reading Strasburg cars 58, 65, and 92 all feature an unusual truck design that was probably specific to the P&R. However, those cars often were sold to other railroads, and one of them ended up on the A,C,&Y. I have a drawing from the 1912 Car Builders Cyclopedia, but I would like to make the trip and get some pictures some day.
I look forward to seeing updates on your progress on these cars. I'm probably 20 or 30 years behind you on era of interest, although I grew up on PC and Conrail from the mid-70's to the mid-80's. But good modeling is good modeling regardless of content.
Jim
