Well, SSC is a private company, not publicly traded, so you can't invest (whether through purchase of shares, notes or other derivatives) through the public markets. Their capital structure is not publicly disclosed (benefit of being a private company), but I imagine that the bulk of the shares are held by the founders with perhaps some outside investment. The only real way to invest would be to approach them individually (or through an institutional investor), but I doubt SSC would go through this unless it was a substantial investment, and I don't think the company is suffering any financial troubles. I also I doubt the shareholders would want to dilute their shares. Of course if SSC keeps expanding, they may considering going public (especially as the founders get older and need to start planning retirement). Still, I imagine SSC is still a tiny company when compared to other toy companies, let alone the broader market. As pointed out above, I imagine they want to keep the company private and intimate.
As for an acquisition, another company may always try to approach SSC to buy the company (and I'm sure they've been approached), but you need a) enough capital and/or financing and b) SSC to be willing to negotiate a deal. Being that SSC is privately held, you can't initiate a hostile takeover or proxy fight. You can't just buy out a privately held company without the target's consent (or at least the consent of the board and majority of shareholders).
Sorry for rambling, but my day job is a M&A lawyer and I seldom get to merge my day job with my collecting.
