You can do this dipole antenna. The total length of a half-wavelength dipole at 433MHz will be 35cm (Lamda=70cm and Lamda/2=35cm).
You have to put two isloators at each end of the dipole.
Also, if you use a 50 ohms coax cable to feed the dipole, you need a balun.
Here are some balun examples:
http://dg7ybn.de/Symmetrising/Symmetrising.htm
I would go for the one named: "Classic half-wave loop Balun for Folded Dipoles", even in the picture is shown a folded dipole.