They wont be exactly the same since yours are aftermarket bronze with the three big lugs, instead of originally one. The should measure either long or short, depending on the version though.Although they do look like the ones on the left, I'm not sure they are the same. I don't have them to hand at the moment, but will have a measure up at the weekend. That could well be the answer though. thanks gortnipper.
I've just fitted these aluminium ones from Andy Molnar. They are half the weight of the chromed brass ones I had on before. They should expand and contract the same as the head. I was instructed to use copper grease.
We'll see how they perform!