Not a stupid question at all. My son is a lefty, and I have switched a few guitars over in my life!
Besides switching the strings around, you also have to reverse the nut. (The nut is the small plastic or graphite strip at the top of the fingerboard that has slots for the strings.) You should be able to pop it out carefully using a little bit of force. If it fits into a channel, just it around an press it back in. If it was glued, use a SMALL amount of glue to put it back in. I have always been just fine using white glue - Elmer's glue. You don't want to epoxy it in there for life, just enough tack to hold it in place. Then, of course, you have to make sure the neck relief is ok after you switch the strings around. Then set the string saddles (on the bridge) to the correct action height for each string. Then reintonate it to get the octaves correct. Then set the pickups to the right height for the reversed strings. All of this is what we call doing a setup. There is a sticky at the top of the "Repair" forum that points you to a couple of web pages where you can read how to do this. Or if you're not a "dig in and do it" person, take it to a guitar store and have it set up. They can probably reverse the nut for you, too.
I hope you're getting a good deal on that gsr200 - they only cost $200 new and if you look around you can find a lefthanded one.
Also, on the low end of the bass price scale, check out the SX basses at
www.rondomusic.net. They sell a lefthanded copy of a Fender Jazz bass (what we call a J bass) for $140.
Good luck, and welcome to Talkbass!