Just to mention some specific examples below 30$
ZY-T08 (About 22,5$ with coupon code)
ZY-T13 (About 22,5$ with coupon code
TR-J18 single thrower (Around 23$)
ZY-T619 (About 23,5$ with coupon code, Single cell thrower, hollow pill and uses 25mm MCPCB (copper MCPCB is not an easy replacement) not as wide reflector but quite deep (limits spill a little bit). Only needs resistance mods to push the stock emitter to 4A, and its close to 3A stock, and it starts on high every time, which is nice for a thrower IMO)
HD2010 (About 28,5 with coupon code)
ZY-T16 (29$, not sure if its cheaper elsewhere)
Most of these lights are quite popular and are easy to find a review off. All can be fairly easily modded to much higher output too.
Most only have about 2amps to the emitter. Most of them have pretty much the same reflector width and throw. HD2010 might be be the brightest light stock if you get the right driver, but that requires luck.