DO NOT BUY FROM MITCHELL'S!!! $300 for a "mint, World War II" M48?! For one, no M48 (except maybe a sniper variant) is worth $300. For another, the things are not World War II rifles. And for yet another, Mitchell's is a bunch of asshats—"teak" stocks my ass, M48 stocks are elm. *grumble* ("Mitchell's Mausers" is a dirty word among the milsurp collector community.)
You can find one in "excellent" condition (aka "unissued") for <$200 on Gunbroker, with all of the standard gear, and you don't have to deal with their fraudulent advertising. Take a couple of weeks to clean it up like I did, and get something that looks even better than a Mitchell's Mauser and for which you can proudly say "this is my baby", or just degunk the action and outside of the stock and sweat the rest out by shooting it.
Anyway, my M48s also love Turk. If you want to be proper, you could use the actual Yugoslavian surplus (mainly from the '50s), which is also a stout load (196gr @ 2600ft/s vs. 155gr @ ~3000ft/s for Turk). The Yugoslavian ammo will rock you back more (more impulse), but the Turk will snap a bit more—with any of them, make sure you have proper stance, or that tactical buttplate will hurt you.
Do not, under any circumstances, fire an M48 off of a benchrest without some kind of recoil dampening mechanism, even if it's just a recoil pad.
The ones currently available at AIM are best described as Fair~Good. Look around at Gunboards, Gunbroker, Auctionarms, and maybe the Surplusrifle forum—at the forums, I'm sure you will be able to find people looking to sell, and GB and AA always have a decent selection of M48s up for auction/buynow.
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If you want to spend $$$ to get the "best" Mauser, look for any of the Czech Mausers (Vz24 and "Persian" Mausers come to mind) or get a Swedish Mauser (downside: 6.5x55 milsurp is kinda scarce).
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Mauser variants to consider:
Turks. Ugly as hell, cheap, usually shitty feeling wood (c'mon, they're like 100 years old by now), GREAT shooters, will probably survive more abuse than you will. ~$100
M48s. Nice Mausers. Intermediate actions make them a bit different for project purposes, but they're still usable. Overall good workmanship, generally in good shape (aside from any which were used in the Yugoslavian civil/ethnic wars), etc. etc.. Great shooters, I already have two and I'm thinking about a third. ~$150
M24/47s. Like M48s, except full-length actions (makes them easier as project guns) and straight bolt handles (I prefer the partially-bent bolt handle of the M48 to straight or full-bent, but w/e). ~$150
EDIT: ALSO INTERMEDIATE ACTIONS, DISREGARD THAT BIT. THINK OF 24/47S AS STRAIGHT-BOLT M48S
Vz24s. Probably the best 8mm Mauser option out there. ~$200
Persian Mausers. BEAUTIFUL. ~$250, $300?
Kar98ks. German Mauser. ~$300? (Not so sure about these, I don't pay much attention to them.)
