I had a similar frame a few years back. It was a Hillman frame built with Reynolds 653 and had Columbus dropouts. I talked to Gordon Hill about why he had mixed Reynolds and Columbus on the frame? He said that the dropouts were probably on hand at the time.
I think your frame has Cinelli lugs and frame fittings and I think you've got the date right - late 80's - early 90's.
You mention Kenevans. I talked to Ken back in the late 80's about him building me a frame. At that time he was trying to flog Reynolds 653 as 'the' frame material. I would say that if your frame is a Kenevans chances are its Reynolds 653 or perhaps Reynolds 531. Ken was also qualifies to build with Reynolds 753 - another possibility. I also know that Ken did paint frames with fades.
My recommendation is to go with Kenevans (usually well built frames) and well known in Australia. The other reason I would go with Kenevans is that you can buy replica Kenevans decal sets from Cyclemondo on
ebay for about $50. You can also get replica frame tube decals from the same source - I'd go for Reynolds 531 or 653.
By the way, it looks like a well built frame. Is there anything under the bottom bracket? Markings - Cinelli - etc?