[jwyss234]

You might see if there is a 3d printing service in the UK. I’ve seen customizers here in the US use services like Shapeways to 3d print parts for their custom figures. Basically, you submit a CAD file and they print and mail it to you. I've never used them myself so I can’t offer more info.

The Black Series Ep. 3 Commander Cody figures has a jetpack similar to Sabine’s. If you find a junk one locally, you might be able to customize it.

After that, the only other options are to sculpt a jetpack yourself or to bite the bullet and order one on eBay.