/routing filter
add chain=bgp-static-out action=accept prefix=68.142.0.0/19 prefix-length=19-24
add chain=bgp-local-out protocol=static match-chain=bgp-static-out set-bgp-communities=11280:115
add chain=bgp-out locally-originated-bgp=yes invert-match=no action=jump jump-target=bgp-local-out
add chain=bgp-out action=accept bgp-communities=11280:115
add chain=bgp-out action=discard
/routing bgp peer set some-peer out-filter=bgp-out
That should do what you want. I'll explain. The routing filter process goes like this:
1. Start in 'bgp-out.' If the routes are originated from 'self' then jump to chain 'bgp-local-out'
2. If a locally originated route is actually redistributed from static, and is present in the 'bgp-static-out' chain then set the BGP community 11280:115.
(bgp-local-out ends. We jump back to bgp-out)
3. Permit routes with community 11280:115.
4. Discard the rest.
Creating a separate bgp-static-out chain lets you utilize that chain like a prefix-list. You can have one rule in 'bgp-local-out' which then matches any routes contained in the chain / 'prefix-list' bgp-local-out.
I haven't tested this but it should work. Hope this helps.