Where can i buy a Hornady Lock N Load modified case for 260 rem?

Wow, every place I could think of is out of stock. You could try calling Hornady directly, they may sell you one but it'll cost more than a retailer would. I think if you have a piece of brass they can make you one. I've heard of them doing that for wildcats although I've never done it.

If no luck with them PM me, I have one you can borrow for a couple weeks if you need to measure distance to lands in your rifle. Just mail it back.
 
Im in the same boat you are except im looking for a 308 case. I have called everywhere looked everywhere and drove everywhere and still cant find one. The other day i found one on ebay but after calling they said 2 to 3 months estimated delivery. We will just have to wait it out.