Well like I said, the bulb you have will be better than nothing
it will suffice. No point in going broke for a bit of an upgrade. You can do that when funds are better.
As far as the basking bulb that's impossible to say. So many factors affect it. For example, in 1 of my tanks I use a regular 60w household bulb and it gets my basking surface to 105.
In my other tank which is wooden and has a different bulb fixture, a 50w reptile basking bulb gets my surface temp to 108.
The only way to find out is to turn it on, and measure the temp over the course of an hour or two. Just make sure you're using an accurate reliable thermometer and not those dial stick on ones.