The landing gear has mostly foam pieces right? Here’s what I would recommend. Get a head gun from Harbor Freight and a small (~1”) putty knife. With those, you can disassemble the pieces carefully and trace them. Use the heat gun to heat up the end up the putty knife until it’s quite hot. The slowly slide the hot knife into the glued joints while lightly wiggling and pulling on the part. Reheat the knife often. You can also directly apply the heat gun to the joints themselves, but be gentle with it and avoid applying heat to and single layer parts like the stabilizers or control surfaces because they will warp pretty easily. Parts that have structure, such as the wing or fuselage, are much less likely to warp. Also, if you’re going to replace a part anyways, it doesn’t matter if it warps.
So start by carefully removing the landing gear using the hot knife technique to avoid damaging the rest of the plane. Once it’s off, use the heat gun to disassemble all the parts of the landing gear. Then trace the parts onto a new piece of foam board from Dollar Tree and cut with an Exacto knife.
Hope that helps.