Currently, a nice condition original '58 Strat will run you between 15 and 20 thousand US dallars. It might also be worth it. One that's obviously been used as a hammer at some point will run you betwwen 8 and 15 thousand, if it's all original. It won't be worth it. Mint, closet classic types are too rare to price tightly, but they'd be over 20 thou anyway. These you wouldn't play anyway, so what's the point? I'd go for a 2 grand Fender Custom Shop '57 relic myself, in sunburst. It'll have all the look, feel, and vibe you could possibly hope for, and believe me, your Dad will freak. I've tried a few, and they are the best of the best, Strat wise. Plus, it's easy enough to find one in a store to check out for yourself. The 50th is a smokin' nice Strat too, but I'd go for the relic at about half the price. You can't go wrong with either of these totally top shelf Strats.
Of course, you might be able to find a '58 tele in nice shape for 8 to 10 grand, if you wanted to go that way. A Tele that old and still totally original is extremely hard to find, but again, relic Tele's, Nocasters and '52s are all out there and very nice.
(BTW, you are a GREAT son