Scale Aircraft Conversions specializes in white metal replacement parts. Its line of replacement landing gear has been expanded to include a set for the ICM 1/48 He 111Z-1 Zwilling.
The set is including a total 20 parts covering the main landing gear struts, fork and tail wheel. I am not 100% sure, but most likely these parts can be used with any of the ICM (single fuselage) He 111.
These parts are drop-in replacements for the plastic parts. To complete the landing gear, there is an extra plastic part that needs to be used. That part (c-10 from the instructions) does not carry weight; hence it makes sense to not replace that plastic part with white metal.