Sorry to resurrect a somewhat old thread, but I have the exact same issue that the OP had and I was hoping for some more information on the subject.
I have a late-model 350 SBC (factory roller cam) that I am using for a 383 build. When speaking to a tech at Crane about a cam recommendation, he advised me not to use stock GM lifters for any cam with more than ~.480 lift (1.5 rockers) because they are more likely to fail after that point. He recommended the same lifters mentioned above, which are $535 from Summit. Here is the Crane listing for those lifters:
Long travel design for 87-98 blocks originally equipped with hydraulic roller cam and lifters. A necessity when camshafts have greater than stock lobe lift or reduced base circle diameter. For use with standard GM alignment bars.
I haven't seen any comparably specified lifters from Comp or any other big-name valve train companies that I have looked into. So I'm wondering, is this really a necessity? Or was the Crane tech simply trying to sell me a really expensive set of lifters? Crane has another set of lifters in their line for a little over $200, which is comparable to most others that I have found from Comp, et al. My phone call with Comp was cut off mid-way through thanks to my cell phone dropping the call and I haven't had time to contact them since.
A good question to ask others here would be: Has anybody used stock GM roller lifters on a cam with valve lift in excess of .480" and had any problems?
Thanks for any information you guys can provide. I will of course check this upon assembly, but I'd rather not have to go through the hassle of returning and re-ordering lifters should I find something wrong; I'd like to try and get the correct lifters the first time.