Ive decided on the klx650 forks for this project for several reasons. The main being: cost, availability and ease of fitting.

They cost me $250 with the axle and triple clamps. These are not as sought after as the wr or cr forks so can be easily found. the wreckers I found had 5 sets in stock, so they arent a big seller. (I ended up buying 2 sets, so I have an extra pair for future projects etc).

The upper and lower bearings bolted straight in, so no bearing swapping.
the stem was almost the correct length, a little shaving of the reataining nut will get around this.

some mods to consider will be this:
1: the xtx axle was thicker so one fork leg will need to be drilled and tapped so the axle screws into it correctly.
2: I'll have to make up a plate to fit the black 4pot brembo caliper to the fork leg, no big problem as it kind-of lines up ok. (will post pics later).
3: a tang will need to be welded to the frame for the steering stops.
4: I'll make up a plate for the steering lock/ignition (hopefully lock will still work ok).

I'm sure the KLX forks will be more suited to the weight of the XTX so hope she will handle ok with these forks.
I'll add more pics of the project as I go.
any comments welcome!