Which shock spring

Hi just wondered if anybody has done this mod and can advize which shock spring i would require for my SDR.
The bike is just used for the road as i have a dedicated track bike.
Im eleven and a half stone with all my kit on.
Ive already changed to a 170/185 and was on the lookout for a 160/185 but ive been offered a 150/185 as a swop by a member on here.
Any help much appreciated

I've fitted a 150/185 on my 07 SDR and weigh just about the same as yourself. It suits me just fine for road and my fairly sedate track excursions.
Worst part is its white not orange. Otherwise great.

While the 150 will likely be fine - I think the 160 you seek is maybe a better choice.

To balance things out, I would also consider going a little lighter up front as well.