We have learned that the 499 shot tube (barrel) can be installed into a 1938B Red Ryder, 105B Buck, as well as the other related Daisys currently being sold. This mod works on the new type guns with the plastic trigger module and "non removable" shot tube.
This requires that the original RR shot tube assembly be removed and a 499 abutment installed in its place. To use the 499 muzzle funnel assembly (makes loading BBs a lot easier plus gives the gun a more finished appearance), the loading door has to be removed for clearance then the shot tube, funnel, and barrel nut can be installed. The original piston is replaced by a 499 piston. This essentially turns a Red Ryder into bargain priced 499. Just like a 499, it's a single shot and uber accurate, but unlike a 499 this gun has a 400-plus fps MV and it's a whole lotta fun to shoot! All the parts required are still available from Daisy at a very reasonable cost- $17.00 plus shipping- and is FAR cheaper than buying a 499, even a used one unless you get real lucky. A 499 spring could be used to replace the stronger Red Ryder/Buck spring if desired.
I first installed a 499 abutment and shot tube into a new Daisy 105B Buck just to see if it would work- and it does. Even using a worn out spring it did 380 fps and is very accurate. Adding a Red Ryder stock or any longer stock really helps the way the Buck feels when shooting it. The Buck stock has a VERY
short LOP. Because the 499 shot tube is short to begin with, it remains unchanged from its original length when using a shorter Buck or the longer Red Ryder as a starting point, so neither gun has an advantage over the other in accuracy.
Some details are discussed beginning here: https://www.thehighroad.org/index.php?threads/putting-a-little-more-power-in-a-15-00-daisy.807316/page-24#post-11039304
The first photo shows the 499 abutment installed into a Buck, the second shows the gun with the 499 shot tube installed.