Have you considered buying yourself a Gen 1+ night vision scope you can get one for about £250.00 to £300 and at the ranges you are probably shooting at you would get loads and no light problems to worry about, this would mean that you would have a dedicted rifle for the purpose so could get expensive.

Or you could get an add on (a night vision device that attaches to your dayscope), often they come up for sale on here

I know its an expense but you cant beat night vision i have just come back from rabbiting tonight and my Dad has 9 rabbits ready for him in the morning all taken with a night vision scope (albeit it is a Gen 2+ unit) it just makes shooting in the dark so much easier

Failing that then what about a torch with a red filter attached, i found that a red filter doesnt seem to bother them as much as white light does.

Whatever works for you, all the best

Vince