hum, the 1:1 top boxes are hard to find, and most of them have been in racecars for 25 years now, and are getting fragile.

You can get them made, a 1:1 top 5 speed dog box is around $5k NZ

There are a couple of larger A series 5 speeds, the 60 and 63 series, (B310 sunny and Australian Stanza) which will bolt up, and generally dont break.

Guys also adapt the Ford or Toyota boxes. Dellow engineering in Melbourne make a bellhousing to put a Toyota box behind an A12