I used to be connected to OASC and to be honest in todays climate anything below 140 wouldn't usually be considered unless your part two was excellent.
I got in as WSO with 107!!! and the competetive mark was 120 in those days.
My pilot score was 164, it just goes to show that it's what slots they have a need to fill on the day. I think it's all down to luck!
I wish you all the best and hope you get what you want. However if they offer you WSO, I would take it. A few of my course mates on IOT and NAv training transfered from WSO to Pilot on IOt and one on the first week of Nav training. Anything is possible.