Hi Jan, very nice picture indeed, thanks a lot for sharing.
As for the Ferrari, I too used to have a toy Ferrari when I was a child, as I was a hot Lauda fan. Unfortunately it has not survived, so I can't say anything about any Heuer sign on it.
Helmet clocks indeed are very nice and mostly seem to have lived on in very good conditions; they still spring up quite regularly on eBay and are not that expensive (or are they, if you consider they're not mechanical?).
Cheers.
Fabrizio