Yes use a transistor,e.g. a 2N700 MOSFET is good
for up to 200mA.
Many IR LEDs can be driven quite hard if pulsed for
a very brief period.
I have seen some with a Spec of up to 60mA or even
100mA I/F (Forward Current), then if you reduce the
Duty (ON Time ) you can increase the current to
double or tripple that,
but it must only be a very short
pulse or the LED may explode
Of course you will need the data sheet for the device
you intend to use just to make sure.
Sony IR protocol SIRC is 38KHz, fairly fast and short
if only a single code burst is used at one time.
You could probably dump up to 500mA or more across
the LED in a 1 OFF burst and not do any harm to the
IR LED. If the LED became stuck ON for more than a
few milliseconds you could kiss it goodbye though.
I'm not saying that this will work on all LEDs so
don't take my word as gospel, for experienced users only
Most Flashing LEDs work this way, the flasher chip inside
pumps the LED with a high current, but only for a split
second.
You can see how much current if you measure it on an
Analogue Multimeter ( the ancient ones with a real meter
)
You may be surprised.