The 2" (50mm) x 1/4" (6mm) thick cast acrylic end cap is rated to 600m while the 50mm aluminum tube is rated to 950m. Would laser cutting a 3/8" (8mm) thick end cap get the rating to at least 950m?
Hi @Marianna, welcome to the forum 
Be aware that 600m is the rating we have provided for our endcap design, but that comes from testing and validation of that configuration, and may include some level of safety factor beyond the predicted failure point to meet our requirements for statistical failure frequency within the rated conditions. We can’t provide a rating for a product we haven’t designed, tested, or validated.
I recommend you play around in the Under Pressure pressure vessel design software, which will provide some theoretical expectations based on the specified dimensions (see the technical details of our flanges and end caps), mounting, and the designed material, e.g.
Note that 3/8" is ~9.5mm, not 8mm. The manufacturing tolerance on the sheet thickness may also be relevant.