I don't usually use ebay but if the parts are significantly cheaper I might be inclined to use one... If I can buy a distributor for $45, I can buy almost 3 of them for the price of upgrading my stock one. That being said, if the stock one is destined to last significantly longer with no issues I'd probably upgrade.
Here's some links:
http://www.ebay.com/itm/HEI-Distribu...5efbc9&vxp=mtr
http://www.ebay.com/itm/HEI-IGNITION...0a6d0c&vxp=mtr
http://www.ebay.com/itm/MSD-8528-Dis...4eb613&vxp=mtr
http://www.ebay.com/itm/Mallory-7758...0beda7&vxp=mtr