Taikou Risshiden (Michiru Oshima)
 

Jabun made a comment on Klondike Audio that Michiru Oshima (composer for Legend of Legaia, ICO) was the composer for a game called "Taikourisshiden". I've done some searching and found a series of Japan-only games called "Taikou Risshiden", which is in at least its 5th incarnation now. But there's very little information about this series.

Does anyone know anything about the music, if any OST or game rip exists? Does anyone have a game from the series?

The music for the first game in this series was indeed composed by Michiru Oshima. And there are two albums that feature music from this game - Taikou Risshiden (KECH-1024), which contains arranged music and KOEI Original BGM Collection Volume 8 (KECH-1048), which contains original BGM.

There has also been game recordings made for the 2nd-5th installment, though I'm unaware if Oshima composed for those as well or not.

It was actually me who mentioned this on your website. And here's a download link for the track I still have, "True Capital": http://www.sendspace.com/file/2jntnp

The old KOEI arrange albums have great instrumenation, so by all means listen to the Arranged album (KECH-1024) for this.

(Selected tracks are also contained on Best of KOEI Vol.4, KECH-1047)