FIRM / Tall box replacement question

[Maryan]

I hope I am not too off topic here, but I saw someone had posted photos of a great "do-it-yourself" tall box she had made herself (congratulations, BTW !) a while ago. I live in France so I can't buy the standard replacement for the FIRM tall box, ie, the Rubbermaid toolbox. I can't buy extra step risers either because there are none (there are only Reebock steps here). I would appreciate any suggestions : I don't want to break a leg using just any old stool ! TIA.Maryan