I bought this one and I use it regularly https://www.amazon.com/Chessex-Role-Playing-Play-Mat/dp/B0015IUAAG/

I use wet erase markers though, since lines are always getting scuffed.

Dice are always a great gift. I like to get a set of metal dice as gift for players. Hollow metal dice are really satisfying to roll and usually have nice decoration.

As for a mat, I use one like this: Chessex Role Playing Play Mat: MEGAMAT Double-Sided Reversible Mat for RPGs and Miniature Figure Games - 34 1/2in x 48in https://www.amazon.com/dp/B0015IUAAG/ref=cm_sw_r_apan_glt_i_FR56J2YPCEW4759QJ1Y2?_encoding=UTF8&psc=1

Note: This is a wet erase marker mat. Don't use dry erase markers on it.

I personally use this http://www.amazon.com/Chessex-Role-Playing-Play-Mat/dp/B0015IUAAG

Get some dry erase markers and the whiteboard cleaner spray and you have an amazing reusable Matt!