My old rule: If Digikey doesn't have it (it seems they don't) then it's most likely a "boutique chip". Meaning it might become unobtainable out of the blue. Then I'd do my darndest to use a lesser but more ubiquitous performer and make it perform via a compensation loop or whatever. At least if it was a design for mass production.
I tried to find darndest in my dictionary but no luck. I think it's darnedest.
Nowadays I've read where frequency agile devices such as cellphones use PLL circuits that operate in the GHz, but I don't know if these are custom circuits just for cellphones or what. In any case, prescalers seem to work.
Mountain speak, closely related to "dang!", something I try to avoid. That was particularly difficult when I laid tile and hit my head on a lava rock wall.
It's mostly custom but you can get devices for WLAN use. They are often overkill and too expensive for an application that is content with the frequency range of a 4046. Sometimes I made PLLs using regular CMOS inverters. That squishes out a few more cents versus a 4046 design and the remaining gates can be rented out. A lot more MHz, too.
Some of the really rock-bottom cost solutions are done either in house or by consultants like me. Most likely these designs won't ever show up on the web because of confidentiality.
However, you may find clever solutions on ham radio sites. Don't know about PLLs but a good start might be the site of the late Jan-Martin, a fellow participant in this newsgroup who died much too young:
Sites like this a full of ideas.
Sometimes even folks who turn every penny during a design can be floored: A long time ago I bought an audio RF clipper. Naturally I had to look inside and it consisted mostly of ordinary 4000 series CMOS logic used in analog functions. Yet this thing works so great that it even impressed a friend who tried it on his E-guitar. He said that their $1000 plus stuff doesn't sound this good.
My frustration was largely because a search on the Philips website turned up two hits on 74HC9046 but neither of them were useful for anything. In fact, the part number is 74HCT9046, and that search yields useful results.