ISM parts help needed

[MrE]

I bought a 2000 transit bus with a 280hp Cummins ISM as a donor bus to replace a seized DD 475hp 8V92 in my motorhome. The speedometer had 211k miles, but Insite shows 680k actual miles. I've decided to do an overhaul, and update the CPL2201 parts with CPL2608 parts so that I can get between 370hp and 500hp, depending on the ecm cal.

I called the local Cummins parts department and ended up sending them an email with the CPL2201 parts that needed replacing, and asked if we could go with CPL2608 parts instead. He responded with "I am unable to do an overhaul with an updated horsepower and torque. Pistons, turbo, injectors head are not a problem, also ecm calibration no problem, however, I cannot get the correct oil cooler housing with the the bypass and regulator for the higher horsepower. Hope this helps somehow. Thanks!" I asked if there was a replacement oil cooler housing that I could use, or if he could supply me with the part number for the discontinued oil cooler housing so that I could try and locate a used one. He failed to provide the part number and responded with "Looks like you must find from a salvage yard. Part is not offered any more from Cummins.".

Is there anyone on this forum that can recommend a competent Cummins parts man that can insure that I get the correct parts for my ISM? I would like to take advantage of the current Cummins overhaul program that's going on until December 31 2016.

2000 ISM-280
ESN: 35011408
ISM CM570
CPL2201

Thank you,
jon