the question pretty much says it all. enough people are having trouble with their cones in the Strikepro snare that I'm sure it would be something that is easy to answer.
The 1st generation STRIKE and STRIKE have columns which were discs glued together..which eventually failed/fell over etc..
The STRIKE SE still use columns but now the discs are tapered to form a stepped cone.
pics attached
For
exact replacement..you would have to contact Alesis and that hasn't been going well lately..
I haven't had a chance but I would measure diameter and length of the SE version and try to match an existing cone..or duplicating the interior of the SE..if possible..
You could also check with the STRIKE Owners group on FB (I don't belong to any Social Media)...maybe someone already has..