However, it would be best to wait until next Spring before trying to hatch any eggs. Yes, as Chuck says, they will be sexually active by 6-7 months, i.e. the pullets will be laying and the cockerel crowing and covering the hens, and possibly the eggs will be fertile. But pullet eggs are small to start with, gradually getting to their full size as the pullet develops. In order for the developing embryo to have as much nourishment available as possible, chicks need the full- sized egg produced by a mature hen in her second year.
Also, if you were to set some eggs next March, for instance, they would hatch in early May, 3 weeks later, when the weather was warmer,the grass was growing, the sun would shine (we hope!) and the chicks could develop better, with fewer worries about cold and wet conditions. This is the natural breeding season, after all, although those of us with incubators can extend this if prepared to give artificial light and heat. Silkies go broody at the drop of a hat, so it should be possible for you to save a lot of money on expensive equipment and have the pleasure of watching them doing the job themselves. You would need to add on 5 months from the time of hatch for any pullets to get into lay that year, so a hatch in early May could be expected to lay around the end of September. If you left it later than that, they probably wouldn't lay until the next Spring, because the light levels would diminish greatly from October onwards and laying is largely dependent on light stimulating hormones.
It might well be possible for you to exchange the cockerel with another belonging to someone else, or rehome him and get a different one. There are always lots of free cockerels in need of good homes, nice birds surplus to requirements, and since Silkies are a popular breed you shouldn't have to look far. I expect your friends on the Forum would be able to help!