Rune Factory 1 ranks in at $20.03, 4 cents above the limit. I didn't particularly see anything closer, anything in the $19.9x that i saw was generally at 19.95. https://www.amazon.com/Rune-Factory-Fantasy-Harvest-Nintendo-DS/dp/B000NVKZ06/

also I'd been meaning to get that game for a while, I've heard good things aboout it and i like the Harvest Moon series