Windows tilt sash quite old need L and R

Thanks for posting. It would be best to see the tilt latch from multiple angles, including its side and underside; that way I can notice any details relevant to the proper replacement. Can you remove a latch and show us such photos? We'll do our best to assist from there. 

Hey there, Bob isn't here today but I'll do my best to help. 

Right off the bat, I can tell you with confidence that we don't sell this exact latch. We also don't sell anything that has no side notches. That's a pretty standard feature on this kind of part, since that's what keeps them secured in the window. To be perfectly honest with you, I don't know how else your latch is staying in place if its sides are totally smooth. That's the main reason we need to see it removed; if your latch doesn't work through standard means, then we have to see what's actually going on so that we can make a better assessment. Otherwise all we can give you is a guess.

That said, I see in your second photo that there is some room for notches. At this stage I don't see any reason why something like our 26-243 and 26-244 wouldn't work, assuming the size is the same. These have a rounded back end, same as yours, and while they do have side "ribs," your window frame has a gap to accommodate them.

At the end of the day, you're going to have to remove one of the originals if you want to get a good replacement. If you can't remove the original to allow for reference then any product you try is going to be a gamble. There's just no way around it. Your next step is to try to find a way to remove them as safely as you can manage. The alternative is to buy a bunch of different parts and hope you get lucky, which I would not advise.

I'll share the specs for our 26-243 and 26-244 below for you to review.

Alternate view of 26-244

Profile view of 26-244