There is probably not a definitive list if that is what you are looking for. It depends on the price and availability of the new part. Everything on my car without exception was rechromed or replaced so I've got a good knowledge base to work from.
Some things like the door handles are readily available and to rechrome them would be prohibitive because of the labor involved in removing and replacing all the locking assemblies. The grill star and barrel is $360 new from Caliber; I would be hesitant to rechrome both of these pieces; it would be very easy for an original star to be broken in rechroming as it is pot metal, and you'd be over $200 easy to replate it. Other pieces like interior trim are NOT readily available, and thus you have no choice but to rechrome in a restoration. Having the exterior brass trim rechromed was not too bad as it is "easy" hand work--straight, flat pieces.
I had all the bumpers on my car repaired and rechromed for $1,100 in Canada at International Bumper in Windsor. The repair takes an experienced person to do. It would probably cost twice that to replace them all with new, and a rechrome job done by a custom plater is usually better then a production run job, because there is more hand work and care put into the final product. Just like painting a house--the builder's paint job is usually less quality then that you will get from paying a professional.
Be wary of "cheap" chrome jobs. It is an expensive process with a lot of hand work. You can easily spend $7,000 to $10,000 on chrome for a 113.
For those that are interested, here are two of the platers I used and I was satisfied with both of their work.
http://www.gravesplating.com/http://www.blplating.comMy bumpers were repaired by:
International Bumper Repair & Metal Work
519-253-4885
1441 McDougall Street
Windsor, ON N8X 3M8
He sends out the plating to someone in Toronto.
Michael Salemi
1969 280SL
Signal Red w/Black Leather
Restored