A very very long time ago I went on 23cms RX with a homemade 4el yagi (tiny, indoors) and borrowed RX converter. This must have been about 1976 or 1977.
There is an relatively inexpensive way of getting on the band (transceive) if you have an FT817 or FT290 to drive it using an SG-LAB transverter. The transverter is about £140 and is made in Bulgaria. Output on TX is a useful 2W. This set-up could be ideal for portable use.
See http://gm1sxx.blogspot.co.uk/2016/08/that-elusive-23cms-beacon-gb3csb.html .
See http://www.sg-lab.com/TR1300/tr1300.html .