Oh, have I got a rail for you
I was faced with the same situation. Older Olhausen table that needed new rails. I put in a lot time researching rails. I spoke with four different table mechanics and got several recommendations from AZbilliards members.
I also spoke with several billiard supply companies.
Virtually everyone agreed that "ARTEMIS K66 PROFILE RAILS" were the answer. I got the information about the "K66 profile" from customer service at Olhausen.
I got the Artemis rails installed and my table plays like a dream. Here's a link to Artemis.com, they are located in Germany but you can get the rails online here in the US.
http://www.artemis-kautschuk.de/en/billardbanden.php
I got mine from Muller Billisrds.com. Muller has by far the best price I could find on an Artemis rail set and shipping is free.
http://www.muellers.com/SearchResult.aspx?searchPhrase=artemis rails
The lower left rail set (36-228) is what I got for my Olhausen table.
One more thing, since you have an older Olhausen table, you would benefit
greatly by having an experienced table mechanic re-ccut the pocket angles,
before replacing the rails. Olhausen customer service ( Tel: 615 323-8522 )
informed me that their older tables had a pocket angle that would often reject ball played with pace. Their newer tables have a new pocket angle.
I took the time to write this long post, because the AZbilliards members took the time to share their information and knowledge with me, when I faced the same problem.
Peace
