I have been looking around for interior also. I found this site http://proseat.com.au/ They do most of their business through ebay I think. For me it is quite affordable too. I haven't bought from them yet but I will soon after finish with the exterior mods.
That is their ebay advertisement.
I am quoting their prices
Pricing as below; All our orders are custom produced in our factory which takes around 2,5-3 weeks to complete, you can choose any colour combination.
$370, any 2 seater cars, utes or front seat only (or rear seats only) custom upholstery retrims/seat covers
$595, any 2+2 or 2+3 seater cars, 4WD
$795, any 2+3+2 seater cars, 4WD
Roof lining, pillar/parcel shelf material, gear/handbrake boots, dash/under dash trims, etc.. are all available, please refer to our other items in store.
I will probably try them out.
Hope that helps