I too have a couple of those. My guess is that they are keychain heads which were used to make standard klickies, using up surplus stock. Since no keychain was ever fitted, the hole isn't there. Perhaps fitting a keychain involved drilling a hole through the hair and into the base of the head, then screwing in the chain attachment. If the hole was not drilled, the klicky would look just like a regular one and could be packed into a set. I don't think Geobra could be cavalier (wasteful) with excess parts back in those days, so it's likely they used surplus parts up. This would also explain why sometimes 'older' klicky parts show up with 'later' ones, such as Flat-edged feet with Molded heads (types 3a and 4a in the chart, MMFs and MMFd).
Mine are types 9 and 10 in the chart (MORono and MORnon); yours, StJohn, is type 11 (MORsos), meaning all three would date from 1978 to 1981 if they fit the pattern -I didn't include either of mine in the 600 on which the table is based, though. Collector shows five fixed-wrist Keychains (none matches my two klickies, nor yours StJohn), four dated 1978, so our keychain heads would fit the timeline.
Anyone with a fixed-wrist keychain (Sylvia?) might be able to help here. I don't collect them, but the few I have don't have this head type, there is a central column into which the keychain screws.
Any more details on yours, Tahra?
Thanks StJohn, great photos!