I need to find out where to purchase a replacement

You can search and purchase a replacement part : http://www.gracobaby.com/store/order/default.asp?N=10418+10413+10421&Ne=11

may this help!

You will need to pry off the cap nut on the end of the shaft (which runs through the two wheel halves. The ONLY tool that will do this is a vice grip and a couple of beers. Also, swearing seems to help.
Clamp the vice grips on tight and rock it back and forth.
You will need to get a replacement cap nut from your local hardware.

You can purchase a complete, new front wheel assembly from Nelson for $12.35. Part number 1609714466.
http://www.lrnelson.com/replacement-parts/

WHAT DOES YOURE MOT TEST STATION SAY ON YOUR MOT

I have a 22" Toro Recycler Lawn Mower with front wheel drive. After many years the original tires wore out, primarily the left front.
After I replaced the wheels the front wheels kept falling off. I learned that Toro uses an unusual two layer washer on the front wheels. You need a) either an exact replacement for this washer OR b) two separate washers. The hole of the washer is 3/8" Everbilt has the smaller flat washer PN 637-009 and the larger washer can be found in the Everbilt PN 281-293. The SMALLER washer must be placed closer to the frame, the larger washer is closer to the wheel. Once this was done it ran perfectly.
Later I found pieces of the original washers in the grass. Toro had the replacement washer available on their website, I was just in a hurry to get the mower back up and running. The Everbilt washers were purchased at Home Depot.

Best and cheapest to fix is to replace vacuum lockers with manual lockers. It is easy to do. Only 6 bolts per front wheel. This is the most trusted way of 100% engagement.

Search eBay or Google it.

The studs press out and in. Perhaps a hammer would work. Replacements studs can be purchased. Need to remove hub, of course.

I have the same problem and contacted Chicco UK directly. Provided that you live in the UK contact the company Storktalk on 01159306700 and the will send you a pair of replacement wheels for £5 including delivery.
Hope that helps
P

Hi there!

I hope i responded quickly. The speedometer needle movement is caused by the speedometer cable that runts to your front wheel's gear unit. Check for the cable that goes near the axle of your front wheel and check that its properly screwed. Put the bike on stand and spin the wheel, if it still doesnt responed. Remove the cable, unscrew it near the front wheel axle first and try spinning the small "squared wire" inside, if you still can't get any action on the speedometer. Then chances are either your speedometer cable is cut in the middle or the speedometer display is jammed (unlikely). Remove the cable from the speedometer unit and check that it is freely rotating. Oil it and put back.
Next, we need to check for the gear near the axle of your front wheel. Screw the speedometer cable to the gear unit near the axle with the other end removed from the speedometer unit. Spin the wheel and check that the inner cable is responding or spinning.. If it doesnt, then your speedometer gears are worn out. Disassemble the front wheel and bring the gear assembly to the nearest parts dealer for purchase. Normally, they don't sell a repair kit so you'll need to purchase the whole gear assembly.

whichever the case, either you purchase a speedometer cable or the gear unit. Seldom will the speedometer unit be destroyed.

pardon me for not organizing this response as you were requesting a quick solution .. so i answered as quick as i could... hehe. Hope this helps!