Instead of all these electromechannical switches, have you looked at some solid state SP2T or higher switches. Digikey has some switches that could be used. How about something like the NJG1519KC1-TE3CT-ND ?

About 0.5dB insertion loss up to 1GHz, 22dB isolation worst case. This switch is rated for 50 ohms, but the insertion loss is low enough to work in a 75 ohm system.

Easiest way to prototype this is to turn it upside down and bend the ground leads to touch a ground layer on a PCB. Then solder 1000pF SMT caps on the control lines to ground. Cut 5 coaxes as pigtails and use 1000pF SMT caps as DC blocks to connect the coax to the RF inputs/outputs. The performance should work well enough as a TV switch. If a PCB is needed then just follow the example in the datasheet.