There is an engine number break. The early unit is much cheaper and appears to be available rebuilt from MB for around $258. The later version doesn't appear to be available rebuilt and has an MB list price of 482. It is available through Bosch and fastlane probably has it much cheaper based upon my price. The two numbers are 000 094 05 48-88 (-88 for rebuilt) and 000 094 10 48.
Bosch Master, ASE Master, L1
33 years MB technician