I would try the single antenna solution first. It's the easiest to install and maintain. And it's going to be easy on the budget. If after installing the 'main' antenna, you can't find an aim point that provides reliable results for every thing you 'need', then a multiple antenna solution can be considered.
The Antennacraft Y10713 is a specialized antenna designed to cover real channels 7 through 13. (Your chances of finding an aim point that 'gets' CH-8 with the 'main' antenna is quite good.)
There are many UHF only antennas that would be viable options for the ION affiliate.
www.tinlee.com is one of a few options for effective antenna combiners. Their AC-7 model is likely the item they would recommend. You would need to contact them for price and availability.