As far as official WOTC character sheets go, all can be found at this link. However, other than the ones you've linked, all the sheets contained there use the full ruleset. Not to mention none contain any story hooks to the Phandalin adventure.
As far as I know, there are no readily available pre-generated basic ruleset character sheets beyond those which you already have.
If you'd like to not waste time and don't mind a few of your players going beyond the basic ruleset, this part of the link above provides various characters with pre-generated sheets for up to lvl 10, far further than you'll need to finish Phandalin.
If you want to stick to the basic rules, you can always use a few of the sheets multiple times. The starter set is only meant as an introduction anyway, to be run up until lvl 5, so your players shouldn't be too bothered with having similar characters. If you choose to have more than two Fighters, you can actually add a bit of diversity by choosing different Fighting styles.
As far as background and personality go, the story hooks presented with the characters you already have are entirely optional. I've played the cleric with one group and am currently DM-ing with another, so I've got experience from both sides. My advice is to let your players decide whether they want to keep the existing background, personality traits and story hooks or create their own. With your more imaginative players making up their own stories, you should have no problems reusing some of the characters multiple times.
In the first group we all chose our own backgrounds and ended up having almost no story hooks left (except for the cleric's relation to the Rockseers). We also had two Wizards in our group, and it worked fine. We still had a lot of fun :) The Wizard is a pretty versatile class already, and their personalities were so different that it didn't at all feel like the same character was used twice.
For the second group, I've offered the players to change whatever they want, but seeing as they were all completely new to the entire concept of D&D they mostly went along with what was written, only changing a few personality traits. As a result of retaining the story hooks, this group has had more success finding/completing various side-quests that can be found in Phandalin compared to the first group. They've had a bit more trouble role-playing the characters, but they got used to them and are having lots of fun themselves :)