Just my two cents, but it's worth a shot.
Go to a custom counter top or cabinet shop and ask them what they use to spray contact cement with. There must be at least one or two of these shops in most areas. I'm sure they spray contact cement because I worked in such a shop years ago, but as a cabinet maker, not a counter top maker. I really don't know what kind of gun they used, only that they used one. I'm almost positive they didn't thin down the cement - just poured it into the cup right out of the can. And yeah, the sprayed on contact cement did have a rough, pebble finished look to it.