It will depend on who manufactured your kit. Some of the kits used reproduction MT-TD parts for the grill and bumpers. They are easy to get, although they may be pricey.
You wrote a “northern company”. If you have a Classic Roadsters Duchess (company is in Fargo North Dakota), your car uses repro original TD parts.
Rechroming is always an option.
Is the body gelcoat? Or paint? If the latter, any rubbing compound will probably help bring the paint back to life. If the former, Meguiars has a line of compounds and waxes for fiberglass, gel-coated boats. I recommend them!
Former Owner of a 1981 Classic Roadsters Ltd. Duchess (VW)
2005 Intermeccanica Roadster
If you own a TDr and are not in the Registry, please go to https://tdreplica.com/forums/topic/mg-td-replica-registry/ and register (you need to copy and paste the link)