JC-55 Roland Jazz Chorus amplifiers are most reliably found on eBay. Because they are no longer in production and due to the age, this model is not sold in most stores. They can usually be found in second-hand markets such as eBay.
These amplifiers can also be found in second-hand music stores, flea markets or online music stores. Online music forums may also have members offering these amplifiers for sale or trade. However, searching these avenues offers no guarantees and can be quite time consuming.
Established second-hand markets, such as eBay, make it easy for consumers to search a wide area for specific items (such as the JC-55), and attract many sellers. You can also try Amazon.com for the same reasons. Other second-hand sources, such as forums or sites such as craigslist.com, typically do not offer the same level of customer protection that larger sites such as eBay or Amazon do.
Local music stores (particularly those that offer second-hand items) may also have JC-55 amplifiers, but this possibility exists on a case-by-case basis. Call the stores before visiting, and compare prices with online vendors such as eBay to ensure you get the greatest deal. Be sure to factor in shipping prices for online vendors.