18650 version i would say yes—will fit, absolutely.
Well the rings are silicone so stretch isnt really a problem. With a zl light i would have to replace a headband every couple of 6months because it would get all stretched out—but that is the fabric part. And That was the only time the light came out of the silicone holder. So, i was never in the habit of inserting and removing the light on a daily basis. The same will be true with a pl47. Takes a little doing to get it in so you probably will want to leave it there. But it doesnt seem over matched or exceeding capacity. It looks like 3/16-1/4” difference in diameter—> zl 603? pl47.
What i did notice right away was—i wear the zl without the top strap. Just headband part & lite. The pl47 without the top strap bounced around alot going up and down stairs. So i tried it with top strap and feels pretty secure. And comfy. Been wearing it for a few hours and pretty much forget it is there (pl47). That said, i have been wearing a headlamp for 10+hours a day for 15-20 years, so your experience may vary.