No I do not know any game scores of standard Shogi prior to the 19th century. And that's quite strange.
You must understand, true, I am not really sure about the situation in the Heian and Kamakura period. But in the Edo era, from the end of the 16th century on, if somebody said "Shogi" he meant the game on 9x9 squares. If he meant another variant, he had to specify. It was the most prestigious game in Japan after Go, which was - of course - the game of games. Shogi - the 9x9 game - was promoted by the Shogunate, the government. Like in Go, the official title of Meijin for the best Shogi player was established and the annual castle tournaments were held, in the presence of the shogun or even the emperor, I'm not sure. At this time the names of the first great players are known. They all played the 9x9 game, not the bigger variants.
My sources? Are you kidding? That's so basic knowledge, you cannot dive into the history of Shogi for one afternoon without knowing that!
And now to your statement about Standard Shogi and Shatranj being "dull" games and that just having a "look at the game" of Chu Shogi suggests Sho Shogi would not stand a chance to rival Chu in popularity." and so on...
Now I have NO opinion at all which one is the "better" game. But you have disqualified yourself so much stating such a nonsense, that I really think that you do not know ANYTHING about what you are talking and just arbitrarily pick it from the web, and actually I do not feel like replying to you any more. Sorry, bro.