If you don't mind doing a bit of modding work yourself you can use this mod to update SRIV.
Download this mod and use the latest version of SR3UnpackTextures to extract all the texture files.
Extract
sr3_city_awld.str2_pc from
sr3_city_0.vpp_pc in your SRIV
packfiles\pc\cache folder. Extract the
sr3_city_awld.cpeg_pc and
sr3_city_awld.gpeg_pc from the
sr3_city_awld.str2_pc.
Use SR3RepackTextures on the extracted
sr3_city_awld.cpeg_pc file and it will update all the textures that are common between SRIV and the hi res texture mod.
Pack the cpeg and gpeg files back into
sr3_city_awld.str2_pc and it should now be compatible with SRIV.