As far as I know the R65 is the only "points in a can" model which means that any ignition system to replace points on the 79/80 model must "fit in the can".
To my knowledge the only people to ever make electronic ignition systems for the "points in a can" were Piranha
who made an optically triggered system of dubious reliability and which, in any event, is no longer available. The second is Boyer-Bransden.
The wife's R65/80 has had a Boyer-Bransden fitted for a few decades, it has proven reliable but I would not fit one now. The reason is simply that the advance curve on the B-B is incredibly aggressive, it begins advancing whilst at cranking RPM and is fully advanced by around 2500rpm - it also gives a bit more advance than stock - at least according to the flywheel marks. I have compromised by the simple expedient of timing at full advance and then ensuring the bike will actually start and if not, back off the timing until it does start reliably. As a result there is a little less than "full" advance at high revs, but the bike starts more willingly without backfiring.
If I had a points in a can model now I would probably leave it alone other than perhaps fitting a generic "transistorised ignition" module so that the points were not switching the coil (and would therefore last near forever), but if I really felt the need I would fit the stick ignition system, or one of the flasher devices from places like Emerald Isle or Siemens.
The only advantage the B-B system has is that it will happily switch the stock twin coils - the others will not.
Given that you would be up for a new coil anyway, the stock harness to connect to the hall effect beancan and the ICU is cheap at around $40, working hall effect bean cans can be had for under $100 (I just bought one from Larry on eBay).
But, and I am going to say this again - I'm not as "in love" with electronic gimmickery as I once was - if it were mine I'd leave it stock other than perhaps fitting the generic module mentioned
http://www.velleman.co.uk/contents/en-uk/p199.htmlhttps://www.ebay.com/itm/Semi-Transistor-Ignition-system-made-in-Japan-DynaSpark-/142300836409or even one of these
https://hobbyking.com/en_us/replacement-complete-ignition-set-for-single-cylinder-gas-engines.html?countrycode=AU&gclid=Cj0KCQiA597fBRCzARIsAHWby0GKy-kHSr3ghdShv3xuKX27Sh30lDtgFwJ3W7I2zay19_js_IHem30aAjX6EALw_wcB&gclsrc=aw.ds&___store=en_us