http://www.realsteel.co.uk/ in the uk, are the main people for street engines.

Danny B can probably sort you out with something imported, he works for http://www.hauserracing.com/

http://www.pawengineparts.com/ do wholesale in the states and can supply you with anything. but you need to call them.

http://www.summitracing.com/ I used these guys and they are very friendly and helpful.

http://www.blowerdriveservice.com/ in the states do the kits.

Ever thought about a holiday, makes importing real cheap!!

You could always order a 1995 6.0 LS1 from Vauxhall out of thier Monaro...