Cheaper is always best.
However, I suspect the TT250 front wheel is the standard, Chinese front wheel. If so, I am pretty confident it will not fit. The hub of any wheel from another mootorcycle must accomodate the RX3 speedometer sensor, brake rotor, et cetera, and this is very unlikely.
Formerly I would allow people to ship me their hubs, and I would build them custom wheels for $55, plus the actual cost of all other parts (rims, spokes, et cetera), plus shipping. However, if I decide to do this project, I would only build and ship complete wheels.
I estimate I could build a complete, 21-inch front wheel for about $325, plus actual shipping costs to the buyer. This wheel would include the following items.
New, complete Zongshen hub, including all bearings and seals
New, alloy, Warp9 rim (black, blue, orange, red, or silver)
New, custom, 21-inch, stainless steel spokes
New, stainless steel, spoke nipples
Actual shipping and packaging costs usually average around $45.
If anyone is interested, let me know, and I will research the matter further.