I'm in the same boat as you and have been trying to find a reasonably priced Explorer I that looks as close to gen as possible. I've reviewed many threads and found helpful posts, but it seems like there is no definitive (or easy) answer on which one is the best. Also I've looked at Intime, PureTime, TS, Marvellous and Toro and have compared their offerings against photos of the gen.
I personally think the best one is the noob version from Marvellous. No, I have not purchased it yet, but from the pics it looks the most gen-like to me. Also, I have not purchased because I am rather new to this hobby and don't know enough to feel comfortable in using any payment method other than CC (plus I like the convenience of CC). Here's a link to the one I'm talking about:
http://v.yupoo.com/photos/mrwatch/albums/6141732/
The following are some things to consider when comparing the Explorer I from different makers:
1. Lume should be blue
2. 3, 6 and 9 markers should not be lumed
3. Rolex crown should be engraved on the crystal in the 6:00 position
4. Engraving on the rehaut should start with the Rolex crown at 12 and the second markers should line up with the Rolex text (1 sec should have the R, 2 should have the O, 3 should have the L, and so on)
5. Engraving on the rehaut around 6:00 should have some bogus serial number
6. Engraved letters on the rehaut should not be tall enough to fill the rehaut...they should maybe take up half the height of the rehaut
7. There should be no engravings on the back of the case
Other members are more than welcome to point out anything I've overlooked or to tell me I'm crazy for liking this noob version. I don't pretend to know everything...I'm here to get some nice reps and learn.