A mirror smooth reflector doesn't work so well with the 64623 bulb. It gives an ugly beam due to the size & shape of that particular filament.
Medium orange peel works well but you could try light orange peel if you can live with some artifacts.
If your determined to try a mirror smooth reflector then you may want to experiment with one of the lower cost ones from
Kaidomain first. If you like what you see, you then have the option of shopping for a higher quality unit when time permits.
This Modamag M2 reflector works well with your 64623 and a light orange peel version is also available. The M2's have a different parabolic profile than other aftermarket reflectors.