I realize this is an old question, but for anybody presently looking for a solution, here's my suggestion. I don't have plans for Tevye's milk cart, but I do have 35 years of theatre experience (both sides of the lights), so my suggestion for you is to either build a small box, open at the top, or if you already have a 3'W X 4'L X 1'H platform built, turn it upside down. Build a simple frame under that box and along the edges out of 2X3 inch lumber with the handles extended forward enough for your Tevye to hold them and walk in front of the inverted box. Now bore holes for a single axle through that "under frame" made from 2X3 inch boards (drill them stacked together, before assembling the frame for easy axle alignment) and put a wooden axle (1 inch dowel rod) through the holes that extends far enough past the sides of the box to attach the wheels. Purchase a couple of 36 inch wooden wheels made for landscaping accents (they're relatively cheap and usually found at landscaping stores and maybe even Harbor Freight Tools). I bought six of them there a while ago for $15 each. In any event, a quick "Google search" should give you ideas where to look. Slide those wheels onto the axles and pin them to prevent them coming off (but still able to turn freely), and then add a simple structure to the top side of that wagon box (a board across the top, front for seating and possibly a rack across the back for tools or bags, etc.) to make it look like the milk cart you want, paint it to look weathered and old, and you're in business.

Edited by Spectrum - 3/04/17 at 2:07am