I am looking to purchase a pda for ebook reading only. Id like to pick up an older model for $50 or less on ebay, to try out before spending alot more on a newer model. I want to be sure im comfortable e-reading on a pda, before spending $150+

However, I want to be able to use Palm EReader

What is the minimum Palm OS that will run EReader?

Also, any suggestions which older models would be my best choice...
palm vx, clie sj20, palm mxxx etc...

Thanks

It appears as though eReader requires OS3 or higher so basically almost any Palm you can buy nowadays. I'd suggest seeing if you can acquire a cheap Tungsten T via ebay as they're going cheap, and you can install most modern software too, they seem to go for about 40 UKP here (which may be slightly over your planned spend though). Other than that I don't know if eReader supports sonys custom hires or not although I guess it probably does so they may be a reasonable option, the T615 or similar (which I'd imagine would be cheap nowadays)

Hope that helps somewhat