Sport weight yarn is a suitable substitute for the handspun.
18 sts (3 pattern repeats) = 2.752.5 inches in pattern on US #3/3.25mm needles
From pattern page on Knitty:
I love this Slanting Shell Stitch pattern as it spirals around in opposite directions on opposite hands in these fingerless gloves. The thumb automatically tucks into a very natural position because of the spiral stitch pattern.
I’ve included instructions for a long glove and a short glove. The only difference between the two gloves is the number of rounds (pattern repeats) worked on size 2 needles in the wrist section of the glove: the long version has 5 repeats or 50 rounds and the short version has 2 repeats or 20 rounds. Because the yarns I used in my gloves were spun at different wpi, and I knit the shorter glove from the thicker yarn, the gauge naturally differs slightly between the two and the narrowing at the wrist is not as obvious.
If you are having trouble making your right hand glove spiral, see this topic in my Twisted Friends group.