You might look up the instructions for the radio you intend to buy. I seem to recall that some can be converted to mode 1. I use a DXe for a small glider I have. Seems to work quite well. The instructions are minimal and I don’t know if you can convert to mode 1 or not. They’re probably on line, though. Further instructions, such as for range checking, can be dug up with a search, but I don’t remember where. Still, it’s only $70 at Tower Hobbies (in the USA). It might help if you gave us a rough idea of your location. For instance, if you were in the Boston area, I could give you one of my old DX5e’s. Those are lousy for airplanes, and have left several in the woods, but they ought to be fine for a footie. My experience is that older servos are fine, but I understand that some of the digital equipment may have compatibility problems. I haven’t encountered those yet.
I notice Tower Hobbies has a two channel, two stick radio for boats, under the Pro Boat brand. I don’t know much about it, but it’s very inexpensive. I’ve seen people use cheezy little radios from Hobby King with success.
Any of the above will probably need batteries.
If you want your footy to be on the light side, you can get very light receivers and servos without breaking the bank. Like 5 or 10 grams, or even less in the case of a rudder servo. Some radios will run on a single lipo battery, which will be much lighter than the old nicads or even nimh. That’s what I have in my 100 gram (more or less) RC DLG (glider). Two lipos is too much voltage for some receivers and servos. You’d probably need a couple of diodes or something to limit it. Or a voltage regulator, which many people use, at least in model airplanes. Most radio gear will run fine on two lithium iron phosphate aka LiFe batteries, which would be my choice if I could find them in the right size. They need a charger which has an LiFe setting. Lipos do too, but that’s default these days.
If you really like your transmitter, you might be able to find a 75mHz receiver on eBay, though AM may make it a little tougher.
Keep in mind that nearly all my RC experience is with flying models, though I’m interested in RC sailboats and would probably do a lot with them if I couldn’t fly my aircraft for some reason. (probably spelled FAA)