Lots available on E-Bay.
The KKK27 was OE on the BMW e23 745i built in 1981 through 1986.
Engine was designated early m102 and later m106.
All used the same Turbo, KKK27.
Seach on E-Bay for "BMW Turbo" and refine it with "e23" if needed.
There is a dedicated web site,
http://745i.scottiesharpe.com
Later,