It seemed as if the most favorable ruling for allowing a melee weapons skill to effect parry is:
1/2 your weapon skill (rounded up) can be added to your attempt to parry with that weapon while you are using it.
A skill of:
+1 or +2 = +1 to parry
+3 or +4 = +2 to parry
+5 or +6 = +3 to parry
Fencing (as a skill using foils/rapiers/sabres) remains unchanged as does the possibility of those weapons breaking when being used to parry.
This keeps the rules simple and clean, without adding new mechanics. modifiers or undue mathematical complications, charts, etc. Second, it keeps Fencing a valuable potential skill but still allows for skilled weapons use of other types of melee weapons to impact defense.
I watched a few videos that showed wood clubs parrying swords, axes parrying spears and daggers parrying spears, swords and maces. So my own hang-ups regarding weapon vs. weapon seems to be unfounded. Give it a shot and let me know your own thoughts, they are always valued.