I'm loosely looking for resources (mostly graphics, but also sounds and music) for two puzzle games — remakes of Stone Age (1992) and Spherical (1989.)

The gameplay of Stone Age (which I intend to mostly preserve in the remake) is simple and a bit reminiscent of the free software Pingus game (and thus the now-classic Lemmings): you guide a tiny dinosaur through a labyrinth of tiles, where certain tiles can be moved (to either of the four cardinal directions, horizontally, vertically, or both.) Such tiles move in the respective direction (either designated, or the one chosen by the player, if there is such a choice) until they hit other tiles (either passable or not) along their way. There're also one-time tiles (which crumble away as the player passes over them), keys and key-locked tiles (which become passable at the expense of one key — either red or green.)

As for Spherical, it's more a platformer. It's feature is that the player may “cast” (and then “uncast”) platforms in his or her vicinity at will, and the objective of the game is to thus prepare the level for the passage of the “spherical artifact” (hence the name) right to the exit.

(For the examples of how the graphics may look like, please refer to the screenshot pages of the MobyGames database records referenced above.)

For now, what I'm looking for is more of a “concept art” than the resources per se. The graphics I'd need are tiles and sprites of 64 × 64 pixels (or so); the sounds are like those for a fantasy game (I'm yet to check OGA for suitable ones); and the music reminiscent of the Good Amiga (Atari) Times.

I seek for resources under a license not stricter than GPLv3 and CC BY-SA (IOW, CC BY-ND will not be suitable), preferably dual-licensed, but I'm also considering a proprietary version of the game (or games), for which I'd need a “commercial” license. (If the project proves to be successful, I hope to pay 200 USD, subject for further negotiation, for such a license.) The game(s) will be released in its (their) entirety as free software in a year or two after the respective “commercial” release(s).

TIA.