These three sites offer replacement parts: www.buckettruckparts.com/ AND www.mobilelifts.com/Truck/Parts.asp AND www.utilitytruck.net/parts.html
Many websites display used bucket truck products online where you can buy them online or email the advertiser/ company to place orders. One such site where you can buy an used bucket truck online is www.truckpaper.com
Penske Truck Rental is a national company that rents bucket trucks: http://www.pensketruckrental.com/
Custom truck parts can be bought online for official dealers or discount online stores depending on what parted are needed/wanted and the type or model of the truck. Parts can some times be found at yard sales or on sites such as ebay. They may also be at or can be ordered at your local vehicle parts store such as princess auto etc.
You can rent a bucket truck in New York at Utility Fleet. They seem reliable and I havnt seen many other bucket truck rentals online. A reference link would be: http://www.utilityfleetsales.com/
A good place to start looking for a used bucket truck is Craigslist. You might also want to try Auto Trader since many vehicles are listed for sale there. There are some websites like, UTruckSales.com that are classifieds site specifically selling used bucket trucks and utility trucks. They have lot's of trucks for sale from reputable used bucket truck dealers like I-80 Equipment. You can also buy directly from the dealers themselves by contacting them. A good place to buy used bucket trucks online is Rock and Dirt. Rock and Dirt is the source for Bucket Trucks for sale and lease since 1950. You can search from 100's of listings for new and used bucket trucks for sale or lease updated daily from 100's of dealers and private sellers.
Many local dealers in your area may carry what you are looking for. The best way to find these dealers would be to use the yellow pages, or talk to someone you know who might have that information. Another option is to shop online, one such online distributer's website is http://www.freightlinertrucks.com/parts-service/parts/overview.aspx
You would have to determine the manufacturer of the engine that runs the bucket then go from there. A company would purchase the International truck and chassis then build the bucket portion themselves.
There are many dealers , dealing in brand new or used bucket trucks. The selection of dealer depends on the locality you are staying in. Some of the reputed companies are Florida Trucks, Skyco equipments, Atlas Truck sales, Inc etc.
The bucket truck designation relates to being part of another truck. The bucket truck is attached to a carrier truck.
Here's a company that services and sells parts for bucket trucks: http://www.alasher.com/parts_service.php
Truck tires are available in tire dealers and online stores. All of them sold tires also with discounts depending on various things. Just ask your local dealers or check online catalogs.
Car Parts Wholesale offers discount car and truck parts for sale online at : http://www.carpartswholesale.com/ You can also order truck parts online at Eagle National Wholesale : http://www.eaglenationalwholesale.com/