Apart from the numbered digest-sized issues in the regular run of the Conan the Barbarian series, to the best of my knowledge, there were only four other digest-sized one-shot editions of Conan comics published by Yaffa/Page Publications:
King Conan #1 (cover price $0.70);
King Conan NN (cover price $0.75) - a reprint of King Conan #1;
Untamed World of Conan (cover price $0.75) - a retitled reprint of Conan the Barbarian #2;
The Legend of Conan NN (cover price $0.75) - a retitled reprint of Conan the Barbarian #3;
I confess I haven't physically crosschecked the contents of the last two digests with their respective parent issues, but given the covers and the track record of Yaffa/Page inhouse reprints it's a safe assumption that the digests are direct reprints of the larger format issues of the original series.
Given that #2 and #3 of Conan the Barbarian earned retitled unnumbered digest editions one might assume that a similar reprint Conan the Barbarian #1 exists. However, Conan the Barbarian #1 was reprinted as Conan the Barbarian #11 of that series. In fact, the publication of Conan the Barbarian #11 as a regular-sized issue ended the run of digest-sized instalments of the Conan the Barbarian series. This is a pattern I've noticed in quite a few other Yaffa/Page series. There are exceptions, but it is nevertheless a quite well-established pattern, which I intend to return to in future blog posts.
The King Conan #1 issue listed above may be numbered but I don't believe there was a second issue, even thought it appears it was projected as a series.
Having said all that, there may indeed be more Conan digests, but I haven't come across any others to date.