I just bought a new starter motor for my 4BD1 after looking for 1 & 1/2 years. The only place in Aus I could find one was from Holden and they were $1800. I just bought one off an eBay shop for $260aud shipped to my door BRAND NEW!.

The good news is the do alternators as well. I paid $1000 for a 120a alt about 3 years ago. I wish I know about these guys then.

They also do normal rover stuff.

Here is the link to the Shop.

eBay Store - ALTERNATOR STARTER AUTO PARTS:

Starter Motor
http://cgi.ebay.com/ebaymotors/New-Starter-Isuzu-NPR-W4-W5-W6-W7-3-9L-5-8L-6-5L-86-97_W0QQcmdZViewItemQQ_trksidZp1713Q2em153Q2el1262Q QcategoryZ33576QQihZ001QQitemZ110356432363QQtcZpho to

Alternator
http://cgi.ebay.com/ebaymotors/New-Alternator-Isuzu-NPR-W4-W5-W6-W7-3-9L-Diesel-90-97_W0QQcmdZViewItemQQ_trksidZp1713Q2em153Q2el1262Q QcategoryZ33573QQihZ002QQitemZ120374298248QQtcZpho to