If you're looking for alternative suppliers of Bukh Parts, it may be worth contacting the following supplier. Although they are based in NZ, shipping times have not been an issue and they provide a most helpful and informative level of service over the phone.
Andy Winter
Director/Engine Sales
The Engine Room Ltd
Ph +64(9)480-2248 Fax: +64(9)480-2258
website: www.theengineroom.co.nz
Bukh Workshop Manual
The workshop manual is available online. Although it's for the 8HP version, it is apparently exactly the same as the DV10LSME (sail drive) engine