Backwoods is correct. You can also buy the individual parts from Webike and assemble them yourself. Here are the part numbers and don't forget the new muffler shield to protect the legs of your rider:
Here is the parts list (part number, description, price)
[95015-82000] PIN B, PILLION STEP,¥115 * 1 = ¥115
[94201-16150] PIN, SPLIT, 1.6X15, ¥27 * 2 = ¥54
[50713-K2E-J00] COLLAR, PILLION STEP(R.), ¥1,188 * 1 = ¥1,188
[50711-K2E-J00] BAR, R. PILLION STEP, ¥616 * 1 = ¥616
[95015-81000] PIN A, PILLION STEP, ¥110 * 1 = ¥110
[90114-MKN-D50] BOLT, SOCKET, 8X28,¥231 * 4 = ¥924
[50715-K2E-J00] HOLDER, R. PILLION STEP, ¥7,040 * 1 = ¥7,040
[18350-K2E-J00] COVER COMP., MUFFLER, ¥10,945 * 1 = ¥10,945
[50712-K2E-J00] BAR, L. PILLION STEP,¥440 * 1 = ¥440
[50710-KTE-910] RUBBER, PILLION STEP, ¥572 * 2 = ¥1,144
[50716-K2E-J00] HOLDER, L. PILLION STEP, ¥7,810 * 1 = ¥7,810
[50714-KBA-930] PLATE, PILLION STEP SIDE, ¥159 * 2 = ¥318
[94101-06000] WASHER, PLAIN, 6MM,¥27 * 2 = ¥54
I can see a problem here as we are getting a rush of new Trail 125 owners who haven't had time to see what has already been talked about when the Trail 125 was introduced in 2021.
Here are the four videos from a couple of years ago that covered the subject:
Assembling the parts:
Installing the pegs:
Installing the rear seat and rack extension:
The payoff for all the work: