You're kind of facing a fundamental tech problem right off the bat here: GBC games only run on a SGB if they're "Dual Mode" (e.g., they can run on a GBC or DMG).
So even if you were to bolt on a border and run it under BSNES/Higan (The only emulator that actually emulates a SGB fully: No other emulator supports the shit the additional SNES hardware was able to provide to some games) or another emulator with limited SGB support (Such as displaying said borders), you're not going to have, you know, GBC colors, which kind of seems to defeat the purpose of figuring out how to do this on a GBC hack of Super Mario Land.
(And in case you want to ask, no, I don't know how to do this: I did very, very minor z80 work on a couple of GB Castlevania games like a decade ago and that's it)
If you're really hellbent on doing this, you could probably make a custom border for an emulator to display around the game. If you're playing it under Windows, BGB
would be a good choice of emulator for that.