Hi there can any one tell me where I can get a performance manafould for twin turbo 2000 model legacy and also would a decat benefit this model as I am new to the subaru world never done much work to them yet untill I bought this with blown head gaskets now fully repaired was a bit different for me but I like a challenge any one got any advise for me

Could try these never used them before. http://www.haywardandscott.com/subaru/legacy.html  Or these 

http://www.demon-tweeks.co.uk/performance/exhaust-manifolds-downpipes/car/subaru/legacy-99-03/2000/2-0

If you want 2nd hand best bets ebay or here in the wanted section :)

 

 

But decat will always help. Just remember you either need to put them on again for the MOT of have a friendly MOT tester thats happy too forget about them :) 

Also you'd need an ECU remap to account for the decat.