Disco 1 - 1" HD Springs

I've got a Disco 1, with 1 year old terrafirma for standrd hight.

I'm wanting to put Heavy Duty springs on it.

I've been adviced to see if I can get 1" lift Heavy Duty Springs as I could keep my shocks.

1st does anybody know where I could get 1" HD Springs,

or what is the biggest springs I can get still using my standard shocks ?

Thanks

I assume from nobody answering is I'm asking the wrong question !

I assume it's probable not possible

i would use std height h/d springs as presumably you want better handling ,been h/d they will lift a little about £50 a pair

ok thanks for that, was looking that way, but thought I'd put it out the the forum for advice, but thanks for getting back

ive used the britpart std height h/d yellow springs very sucessfully on my own and others with gas shockers