Change you toll deny to 1X (MMC702, IT 4.8.1) and set to yes

Enable X as a wildcard for digits 0-9 (MMC 704, IT 4.8.3)

Set 1200 as yes (MMC703, IT 4.8.2)

Now anything starting with 1 will be denied *except 1200*

The toll allow table will override the toll deny table.